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To investigate the pathogenetic role of human T lymphocyte virus type I (HTLV-I) in central nervous system disease, a rat model for HTLV-I-associated myelopathy/tropical spastic paraparesis, designated as HAM rat disease, has been established. Wistar-King-Aptekman-Hokudai strain rats with induced HTLV-I infection develop a chronic progressive myeloneuropathy with paraparesis of hind limbs after an incubation period of 15 months. In the affected spinal cord in these rats, white matter degeneration, demyelination and vacuolar change with microglia/macrophage infiltration are present as are the provirus DNA and the virus mRNA. To identify infected cells in the affected lesions, we carried out in situ hybridization of amplified fragments of the provirus DNA by polymerase chain reaction on thin sections, plus immunohistochemistry on the same sections. The provirus DNA was localized in some microglia/macrophages in the spinal cord lesion. In addition, the HTLV-I provirus was clearly evident not only in ED-1-negative lymphoid cells but also in ED-1-positive macrophages from lymph nodes. These observations suggest that cells of microglia/macrophage lineage may be one of dominant viral reservoirs in the spinal cords and lymph nodes in HAM rat disease. These infected microglia/macrophages may relate to cause the myeloneuropathy through neurotoxic cytokine synthesis. Received: 14 January 1998 / Revised, accepted: 30 July 1998  相似文献   
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(Received for publication on Aug. 19, 1998; accepted on Mar. 11, 1999)  相似文献   
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Objective To identify factors associated with pneumomediastinum during management of connective tissue disease (CTD)-related interstitial lung disease (ILD). Methods Patients diagnosed with pneumomediastinum after the initiation of corticosteroid therapy for their CTD-ILD were enrolled. The baseline characteristics of patients who developed pneumomediastinum after the initiation of corticosteroid therapy (n=13, all occurring within 120 days) were compared to those of patients who did not develop pneumomediastinum (n=49). A multivariate logistic regression analysis was performed to identify factors associated with pneumomediastinum. A receiver operating characteristic (ROC) curve analysis was also performed to assess the predictive performance. Results The body mass index (BMI) [odds ratio (OR) (95% confidence interval (CI)) 0.482 (0.272-0.853)] and serum lactate dehydrogenase (LDH) [OR (95% CI) 1.013 (1-1.025)] levels at baseline were identified as independent factors associated with pneumomediastinum after corticosteroid initiation. The optimal cut-off points of the BMI and LDH levels for predicting pneumomediastinum development, as estimated by the Youden index, were 20.2 kg/m2 and 378 U/L, respectively. LDH showed a sensitivity of 61.5% and the highest specificity of 87.8%. Importantly, combining these markers resulted in the highest sensitivity of 100% and a specificity of 71.4%. Conclusion A low BMI and high serum LDH levels at baseline are useful predictive factors for pneumomediastinum development in CTD-ILD patients.  相似文献   
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BackgroundLimited epidemiological evidence has suggested a positive relationship between night shift work and the risk of cancer. Herein, we investigated the prospective association between different forms of work schedule and the risk of numerous cancers and all-cause cancer among Japanese men and women.MethodsThis cohort study included 45,390 working men and women aged 40–79 years and registered in the Japan Collaborative Cohort Study (JACC Study). The Cox proportional hazards models were used to calculate the hazard ratios (HRs) and their 95% confidence intervals (CIs) for incident cancer among those who reported engagement in night work and rotating shift work for their longest occupations compared with day work.ResultsWithin a median follow-up duration of 14.2 years, 2,283 (9.4%) men and 1,309 (4.5%) women developed cancer. Among men, rotating shift work was significantly associated with increased risk of esophageal cancer (HR 2.47; 95% CI, 1.42–4.31) and decreased risk of liver cancer (HR 0.54; 95% CI, 0.30–0.98). Also, rotating shift work tended to be associated with the increased risk of prostate cancer (HR 1.42; 95% CI, 0.95–2.12). Night work and rotating shift work were not related to the risk of all-cause cancer in either sex.ConclusionRotating shift work might contribute to the increased risk of esophageal cancer and prostate cancer and the decreased risk of liver cancer among Japanese men.Key words: night work, shift work, esophageal cancer, liver cancer, prostate cancer, cohort study  相似文献   
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Objective Patients with Prader-Willi syndrome (PWS) are known to have a high mortality rate. However, little is known about the exact reason for this, particularly in adults, because so few reports have been published. The present study examined cardiovascular abnormalities to determine the cause of death in adults with PWS. Methods From September 2017 to April 2019, a total of 18 adults with PWS, and, no history of cardiovascular diseases, were enrolled. We investigated the levels of the cardiovascular biomarkers: high-sensitivity C-reactive protein (hs-CRP) and troponin T (TnT). To estimate the cardiac function, we measured the left ventricular ejection fraction (LVEF), global longitudinal systolic strain (GLS) of the left ventricle, ratio of peak early mitral filling velocity (E) to early diastolic mitral annular velocity (E/e'' ratio), mitral annular plane systolic excursion (MAPSE) and tricuspid annular plane systolic excursion (TAPSE) using standard and tissue Doppler echocardiography. Results The mean patient age was 28±9 years old. There were 11 men, and the mean body mass index was 45.1 kg/m2. Dyslipidemia (82%), diabetes mellitus (82%) and hypertension (83%) were commonly found as comorbidities. Most patients had elevated levels of hs-CRP (mean 1.007±0.538 mg/dL). The LVEF (mean 61%±5%) showed normal values, while the GLS (mean 15.0%±3.0%) was decreased. The TAPSE was mildly reduced (mean 16±3 mm). Conclusion These results suggest that subtle cardiovascular abnormalities have already begun in young adults with PWS. We need to manage obesity and the resultant obesity-related disorders in order to prevent heart failure and coronary atherosclerosis in PWS patients.  相似文献   
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